From the Guidelines
Antiplatelet therapy with aspirin should be initiated as soon as possible after acute ischemic stroke, with a loading dose of at least 160 mg, followed by a daily dose of 81-325 mg, as recommended by the most recent guidelines 1. The primary goal of antiplatelet therapy in acute ischemic stroke is to prevent recurrent strokes by inhibiting platelet aggregation and reducing the formation of new blood clots. Aspirin is the most extensively studied and recommended antiplatelet agent for this purpose, with a significant body of evidence supporting its use, including studies such as the EARLY trial and the FASTER pilot trial 1. Some key points to consider when initiating antiplatelet therapy in acute ischemic stroke include:
- Aspirin should not be given to patients who will receive thrombolytic therapy (like tPA) until 24 hours after the thrombolytic infusion is completed, or to patients with hemorrhagic stroke.
- For patients unable to take aspirin due to allergies or intolerance, clopidogrel (75 mg daily) can be used as an alternative.
- In high-risk patients, particularly those with large artery atherosclerosis, dual antiplatelet therapy with aspirin plus clopidogrel may be considered for a short duration (21-90 days) following the acute event, as suggested by recent guidelines 1 and studies 1. It is essential to weigh the benefits of antiplatelet therapy against the risks, particularly the risk of bleeding complications, and to carefully select the most appropriate patients for dual antiplatelet therapy. Overall, the use of antiplatelet therapy, particularly aspirin, is a crucial component of acute ischemic stroke management, and its early initiation can help improve outcomes by reducing the risk of recurrent strokes.
From the FDA Drug Label
Clopidogrel is a P2Y12 platelet inhibitor indicated for: Acute coronary syndrome –For patients with non–ST-segment elevation ACS (unstable angina [UA]/non–ST-elevation myocardial infarction [NSTEMI]), clopidogrel has been shown to reduce the rate of myocardial infarction (MI) and stroke. (1. 1) –For patients with ST-elevation myocardial infarction (STEMI), clopidogrel has been shown to reduce the rate of MI and stroke. (1.1) Recent MI, recent stroke, or established peripheral arterial disease. Clopidogrel has been shown to reduce the rate of MI and stroke. (1.2)
The role of antiplatelet agents during acute stroke is to reduce the rate of myocardial infarction (MI) and stroke.
- Key points:
- Clopidogrel is indicated for patients with recent stroke.
- The recommended dosage for recent stroke is 75 mg once daily orally without a loading dose 2.
- Antiplatelet therapy should be initiated as soon as possible after the onset of acute stroke symptoms. However, the provided drug labels do not directly address the use of antiplatelet agents during the acute phase of stroke. Main consideration: The use of antiplatelet agents in the setting of acute stroke should be individualized, taking into account the patient's specific clinical circumstances and the potential benefits and risks of therapy 2.
From the Research
Role of Antiplatelet Therapy
The role of antiplatelet therapy during acute stroke is to reduce the volume of brain damaged by ischemia and decrease the risk of early recurrent ischemic stroke, thereby reducing the risk of early death and improving long-term outcomes in survivors 3, 4, 5.
Benefits of Antiplatelet Therapy
- Decrease in death or dependency at the end of follow-up 4, 5
- Reduction in early recurrent ischemic stroke without a major risk of early hemorrhagic complications 3, 4, 5
- Improvement in long-term functional outcome, reducing the proportion of patients dead or dependent 6 months after the stroke 3
- Increase in the odds of making a complete recovery from the stroke 5
Antiplatelet Agents
- Aspirin is the only antiplatelet agent which has been evaluated adequately in acute ischemic stroke 3
- A dose of 160-300 mg is required to achieve rapid inhibition of thromboxane biosynthesis 3
- Clopidogrel and aspirin may provide greater protection against subsequent stroke than monotherapy, especially when used in the early acute ischemic phase 6, 7
Safety of Antiplatelet Therapy
- Antiplatelet therapy might also increase the risk of fatal or disabling intracranial haemorrhage 4, 5
- However, the risk of symptomatic intracranial hemorrhage is small, with 2 cases for every 1000 patients treated 5
- Loading with 375 mg of clopidogrel and 325 mg of aspirin appears to be safe when administered up to 36 hours after stroke and transient ischemic attack onset 7